The importance of integrated circuit semiconductors in the electronic industry is well known. These circuits have revolutionized the industry. Employed in miniaturized form and made into chips these circuits can be utilized in great numbers in very little space such as on printed circuit boards.
Integrated circuits formed into chips may be packaged in a rectangular plastic carrier having conductive leads extending from each marginal edge thereof. In order to connect this leaded chip carrier to a printed circuit board an electrical connector or socket is employed which provides mechanical and electrical connection between the conductive leads of the chip carrier and conductive traces on a printed circuit board.
A typical leaded chip carrier, such as that shown in U.S. Pat. No. 4,465,898, includes an enclosure or body typically formed of an epoxy plastic and having a plurality of J-leads extending therefrom around its periphery. Connectors for accommodating plastic chip carriers typically include a rectangular (usually square) housing which supports around the perimetrical edge thereof a plurality of spring contacts. The body includes a central cavity into which the spring contacts extend. The spring contacts of the connector are biased into the cavity of the body such that upon insertion of the plastic chip carrier into the cavity there is substantial engagement between the J-leads of the plastic chip carrier and the spring contacts of the connector. In order to insure adequate electrical connection between the spring contacts and the J-leads a high degree of insertion force is necessary to insert the plastic chip carrier into the connector. While the necessary force may vary from connector to connector and carrier to carrier depending on construction, thickness and material composition, a high degree of manual force is usually necessary to insert the plastic chip carrier into the connector. That is especially true with plastic chip carriers having leads which may number as high as 68 or more as is now desired for increased circuit density. It is apparent that the force needed to urge the plastic chip carrier into engagement with the contacts of the connector may be so great as to render manual insertion by the user difficult. As difficult as insertion may be, extraction of the plastic chip carrier from the connector is even more difficult. Leaded plastic chip carriers, presently on the market, require the use of an extraction tool to remove the chip carrier from connector. Use of an extraction tool is necessitated in that the force to remove the chip carrier from the connector is so great that the user requires a mechanical advantage to make such extraction. A typical extraction tool is a wheel puller having a screw-type shaft which supplies the mechanical advantage.
It is also apparent that the force exerted on each of the leads of the chip carrier by the individual contacts is also great. Thus, upon movement the contacts into engagement with the leads of the package significant deflection of the contacts take place. Without controlling the amount of deflection and direction of the deflection of the contacts, the contacts may be damaged upon repeated insertion and removal of the chip carrier in the housing.
It is accordingly desirable to provide a chip carrier connector which retains the carrier in the housing with a high degree of retention force, yet is operable without need of a special insertion and extraction tool which provides a mechanical advantage. Also, the connector should accommodate contacts which are required to exhibit significant deflection without damage thereto.